Releasable slide fastener



y 1961 l B. HARMON 2,983,017

RELEASABLE SLIDE FASTENER Filed July 5, 1958 FIG. 2. 26

INVENTOR BERNARD HARMON BY Z z W ATTORNEY such as other portions of the cam face. clothis caught in the-slide fastener the pull tab is: swung to itsnorrnally ifioper'ativeposition .andthe release portion of its .cam face is 'thereby brought into engagement Effectfifi? rende ringth'e i il 9 7'. 4 Each of'these tw'o' nie'thods' may be practiced in several United States Patent v 2,983,017 *R-ELEASABLE SLIDE FASTENER Bernard Harmon, 409 Pearl St., New York, N.Y. Filed July s, 1958, Ser. No. 746,424 2 Claims. (c1.24-20s.14

This invention rel tes to a releasable slide fastener construction.

The principal object of this invention is the provision of a releasable slide fastener which incorporates cam means for'freeing it from entangled cloth. It is frequently the case that the cloth of the garment in which a slide fastener or closure is provided becomes caught or entangled in the slide fastener; When this occurs, great difficulty is encountered in freeing the slide fastener from the cloth or the cloth from the slide fastener, as the case may be.- .Itis' the'pri ncipal object of this invention to provide means *for'freeing the slide fastener from the cloth without the cloth. I p

More specifically, the present invention involves the use of cam means for achieving this purpose. The invention may be practiced in two ways: in. one way the cam is maintained in normally operative position at all times except when it is desired to free the slide fastener from the cloth and in such case the cam is moved into inoperative position; 'inthe second way, the cam isprovidedwith bothrelease and locking portions and the release portion 'of the cam is'maintained in normally inoperative position at all'times except when it is' desired to free the slide fastener from the cloth and only then is it moved into operative position. The first of these two damage either to the slide fastener or to methodsfis' preferred, but the second method may be employed if and as desired; I

More specifically still, the present invention involves the use ofa pull tab with a cam face which is engageable with and disengageab'le'from the stringers'or at 1 least one of them, When the first method is'pra cticed, the cam facejof the pull t'ab is maintainediin engagement with thestringer; or stringers at all times during the normaluse ofjthe slide fastenen; The stringers are thereby maintained under a predetermined pressure and .tension.

tionmjlocking engagement with fastener elements of a Whencl'oth is caught'in the; slide fastener, the pull'tab is swung to a normally inoperable position and its cam face is'thereby moved out of engagement with the'stringer oi stringers. Thestringer's arenow released from tension .and the jclothmay be disengaged or disentangled therefrom.- lnthefsecond method of practicing this i nvention, the release portion of the cam face is normally out of engagement with the stringers and said stringers are maintained under appropriate tension by other means But, when the with theistringers tor at; least one of them. f A'cam action'is' therebyetfected which tendstojseparatethe two them 'from-tliecloth.

51: 1 partsof thefshell or slider -beyond the extent of their. normal separation 'andfladditional clearance is' thereby V ,Patented May 9, 1961 ways. The pull tab may be provided with a cam-faced tion which is engageable with the other of the two stringers, orit may be provided with two cam-faced formations which are engageable with both stringers simultaneously. Another possibility is the provision of a single camfaced formation which is engageable with both stringers at the same time. Still another possibility is the provision of cam rollers to facilitate relative movement between the slider and the'strin'gers.

A corollary object of this invention is the provision of a releasable slide fastener which incorporates cam means adapted to perform two functions: The first is to free the slide fastener from entangled cloth 'as'first above described. The second is to provide a locking action between the slider and the fastener elements carried by the stringers. I

In'conventional slide fasteners a locking pin is provide'd on the slider for interlocking engagement with the fastener elements on the stringers. In the present invention the cam elements are adapted to tightly'engage the fastener elements so 'as' to prevent slidable movement of the slider relative to the stringers. I

These and other possibilities are all encompassed within the broad scope and spirit of the present invention and the forms of the invention which are herein specifically illustrated and described are merely illustrative of the invention and not limitative thereof. For purposes, therefore, solely of illustration and not of limitation, several forms of the invention are shown in the drawing in which:

Fig. 1 is a face or top view of a slide fastener incorpora'ting the features of one form of this invention.

Fig. 2 is an enlargedsection on the line 22 of Fig. 1. Fig. '3 is an enlarged section on the line 33 of Fig. 1, showing the cam member of the pull tab in engagement wlth the fastener elements of'one of the stringers.

Fig. 4 is a perspective view of the pull tab,showing the cam-shaped formation which is providedthereon.

Fig. '4Ais a similar'view of a pull tab showing a modified cam-faced formation. 7

Fig. 4B }'is' an enlarged fragmentary sectional view showing the locking portion of said cam-faced formastringer. I Fig. 4C is a similar'view showing the pull tab moved degrees from its. Fig. .4B position to disengage the cam formation from the fastener elements 'to permit sliding'ofithe slider element. I

' Fi 4D is a similar viewshowing the pun tab moved 180degnees from its Fig. 4B position'to provide a camming" action against theffasten'er elements sufficient to spread the slider body. apar vorder to release a piece I Fig J4E shows a' simila'r pull tab'withtwocam r6 .m tions'. 1

y I 'forrnati ns engagement with both rows of .fastener el 'Fig. 7 it aside View T f a 51m r lid er, v

emai s imner erate.

and a pull tab 24 by which said slidable member is actuated. The stringers are formed of the usual elements, to wit: tape 21a and fastening elements 21b, and also tape 22a and fastening elements 221:. The slidable member 23 is a shell which has an upper wall 23a and a lower wall 23b. These walls are spaced from each other to'accommodate the stringers between them. This slidable member is also provided with conventional cam means for camming the fastening elements 21b and 22b into and out of engagement with each other. The pull tab 24 is pivotally mounted on a horizontal or transverse pivot 25 which is supported on a bracket 26. This bracket 26 is integral with the bottom wall 23b of slidable member 23 and it projects upwardly through an opening in the top wall 23a thereof. The top and bottom walls are connected to each other only at their forward ends, which is conventional. Pull tab 24 may be swung a full 180 degrees on its pivot 25, from one parallel position to anoth er parallel position with respect to the slidable, member 23 and to the stringers 21 and 22. See Fig. 2. o

It will be noted that an opening 30 is provided in the top Wall 23a of the slidable member, immediately above the fastening elements 21b of stringer 21. It will also be noted that a cam 24a is provided on the pull tab 24 immediately adjacent its pivot 25. The cam face of cam 24a is substantially semi-circular and it is equidistant for an angular distance of approximately 180 degrees from pivot 25. When the pull tab is in one of its horizontal positions, cam 24a will project through hole 30 and engage the fastening elements 22b of said stringer 22.

This arrangement may be utilized in either of the two ways first above described. If it be assumed that the cam is in engagement with the fastening elements when the pull tab is in a normally operative position (while open ing or closing the slide fastener), then the engagement of the cam with the fastener elements should be, such as to render it possible to move the slidable member relthat is parallel to the stringers 21 and 22, its

ative to the stringers without undue friction. The cam should merely maintain the fastener elements under a predetermined amount of tension, consonant with the proper functiom'ng of the device. When the pull tab is swung to locking position, the cam tightly engages the fastener elements and locks the slider against movement relative to the stringers. When the pull tab is swung approximately 180 degreesfrom its lockingposition toits normally inoperative position, then the cam disengages the fastener elements and releases the tension thereon.

Sufficient clearance is thereby provided for the stringers in the slidable member and for any cloth that may have become entangled between the stringers or in the. slidable member, to render it possible to free the slide fastener from said cloth or said cloth from the slide fastener. The pull tab may now be swung back to its normally operative position, with its cam in engagement with the fastener elements of one of the stringers; The stringers are now maintained under adequate tension and the device is now once again ready to perform properly.

structure and function, not only to eachother but also to the. cam formation shown in Fig. 4A. Whena single It is immaterial whether cam" 24a. is on the rightside or-the left side of ,thepull tab. Whenit is on one side it'engages the fastener elements of one o f the stringers and when it is on the other side it engages the fastener elements of the other stringer. It is immaterial. which fastener elements are P ever, to engage the fastener elementsof both stringers simultaneously, and in such case two. cams shouldbe provided on the 'pull tab, one on each side thereof. 5 Pull tab '34, which corresponds to pull' tab 24, is therefore provided with a pair of I one on each side thereof. The, top wall 33a of slidable member,33 is accordingly provided with two openings .E'a d? .6. re pe v ly in adOK-Q JY o e n mies-su h as Gam g 30 rst ab ve descr bed. omiwa li .331 ;Bivo. a1 members. SfZuengagen a bracket 3&supporting the pulltabvon the. topwallof cams 34a and 34b. respectively,

engaged. It may be desired, howbody through which the cam mounted on V v tenerelements, and a pulltab pivotally mounted onsaid the slidable member and the cam faces of the two cams 34a and 341; are equidistant at all points from said pivotal members 37. These cams project through openings 35 and 36 and engage the fastener elements of both stringers at the same time. See Fig. 6. As has above been incated with respect to the pull tab having only one cam, the pull tab now under discussion may be provided with cams either on top or on the bottom. When the cams are provided on the bottom of the pull tab, they are normally in engagement with the fastener elements when the pull tab is in normally operative position. When the cams are provided atop the pull tab,.they are normally not in engagement with the fastener elements when the pull tab is in normally operative position.

Fig. 4A discloses a cam which has both release and locking portions. Pull tab 24b is constructed basically like pull tab 24 shown in Fig. 4, and it is provided with transverse pivot elements 25a. Cam 240 has two distinct camming portions which are diametrically opposite each other. The lower relatively low portion 24d of the cam is its locking portion. Upper relatively high portion 24:; is its release portion. Between these two cam portions is a low portion 24f which merely guides the stringers and holds them in line within the slider body. When locking portion 24d of the cam is in engagement with the fastening elements on the stringers, said fastening elements are tightly engaged, and the slider is locked in place. See Fig. 4B. When the pull tab is swung upwardly degrees in counter-clockwise direction to its position in Fig.

40, low cam portion 24 will engage the. fastener elecaught in it. See Fig. 4D. Cam portion 24e exerts a strong force upon the fastener elements sufficient to space them from the top of the slider body and thereby free the entangled cloth. It will of course be-understood that the wings of the slider body are spread. apart when either of the cam portions is caused to engage the fastener ele ments. 1 i

The foregoing is illustrative of preferred, forms of this invention, and as has already been indicated these preferred forms may be modified. in many ways. within the broad coverage of the invention. For example, Fig. 4E

discloses a pull tab identical with that shown inliigl 4A but having two cam formations thereon instead of only one. This would be" analogous to thelr elationshipbetween the pull tab shown in Fig.5 and thatfshowfiin Fig. 4. i The two camfformationsin Fig. 4Efarelideritic'al. in

cam formation is used, a single opening in. the, slider formatioii may reach the fastener elements, will sufiice. 'Where two camforr'nationsareused, two openingsin the slider body are required. I 7 I clairn:

l. A slide fastener offthe character; described, comprising a pair of stringers, cooperative/fastener elements secured to s aid str ngers, a one-piece slide; body slidably said stringers for engagement. with said fasslidei body, said sliderbody having an openingformed therein and. said pull tab having a camformation thereon which is engageable with said fastener. elements through said opening to lock the slider body inplace, relative to the stringers, a second opening being provided in said slider y ch s q dt am .fcrmuiqnrb iesi rqtis .9 sa d null; tab or en a ement. t rou h; a drs sp opening with said fastener elements to cooperate with the first earn formation in looking the slider body in place, each of said cam formations being provided with two spaced cam faces and a dwell between them, said cam faces being alternately brought into engagement with the fastener elements by pivotal movement of the pull tab, one of said cam faces constituting a relatively low cam formation which is adapted-to frictionally engage the fastener elements with sufficient force to lock the slider body in place, the other cam face constituting a relatively high cam formation which is adapted to engage the fastener elements with sufficient force to spread the slider body apart and thereby to release any cloth entangled therein, said dwell being lower than the relatively low cam formation so as to fall short of locking engagement with the fastener elements, thereby permitting slidable movement of the slider body relative to the stringers.

2. A slide fastener of the character described, comprising a pair of stringers, cooperative fastener elements secured to said stringers, a one-piece slider body slidably mounted on said stringers for engagement with said fastener elements, and a pull tab pivotally mounted on said slider body, said slider body having an opening formed therein and said pull tab having a cam formation thereon which is engageable with said fastener elements through said opening to look the slider body in place relative to the stringers, the cam formation being provided with two spaced cam faces, said cam faces being alternately brought into engagement with the fastener elements by pivotal movement of the pull tab, one of said cam faces being adapted to frictionally engage the fastener elements sufliciently to look the slider body in place, the other cam face constituting a larger cam formation than the first cam face and being adapted to apply a stronger camming force to the fastener elements sufiicient to spread the slider body apart and thereby to release cloth entangled therein, said cam formation being provided with a low spot between the two cam faces, said pull tab being pivotally movable to disengage the two cam faces from the fastener elements and to position the low spot in facing relation to said fastener elements, said low spot falling short of looking engagement with said fastener elements and permitting slidable movement of the slider body relative to the stringers.

References Cited in the file of this patent UNITED STATES PATENTS 1,991,831 Winterhalter Feb. 19, 1935 2,042,325 Prentice May 26, 1936 2,855,651 Deshaw Oct. 14, 1958 FOREIGN PATENTS 595,18-6 Germany Apr. 3, 1934 838,882 Germany May 12, 1952 

